Geophysical survey to estimate the 3D sliding surface and the 4D evolution of the water pressure on part of a deep seated landslide

International audienceGeophysical surveys were conducted on the very unstable front part of the La Clapière landslide in the French Alps (Alpes Maritimes). The electrical resistivity survey was carried out to obtain, for the first time on this deep-seated landslide, 3D information on the slipping surface and the vertical drained faults. Moreover, we planned to follow within time (6 months) the evolution of the saturated zones (presence of gravitational water) and their percolation into the shearing zones. Our 4D results showed the importance of the complex water channelization within the slope and relation to geological discontinuities

VIP Enhances Phagocytosis of Fibrillar Beta-Amyloid by Microglia and Attenuates Amyloid Deposition in the Brain of APP/PS1 Mice

Vasoactive intestinal peptide (VIP) is a multifunctional neuropeptide with demonstrated immunosuppressive and neuroprotective activities. It has been shown to inhibit Amyloid beta (Aβ)-induced neurodegeneration by indirectly suppressing the production and release of a variety of inflammatory and neurotoxic factors by activated microglia. We demonstrated that VIP markedly increased microglial phagocytosis of fibrillar Aβ42 and that this enhanced phagocytotic activity depended on activation of the Protein kinase C (PKC) signaling pathway. In addition, VIP suppressed the release of tumor necrosis factor alpha (TNF-α) and nitric oxide(NO) from microglia activated by combined treatment with fibrillar Aβ42 and low dose interferon-γ (IFN-γ). We utilized an adenovirus-mediated gene delivery method to overexpress VIP constitutively in the hippocampus of APPswPS1 transgenic mice. The Aβ load was significantly reduced in the hippocampus of this animal model of Alzheimer's disease, possibly due to the accumulation and activation of cd11b-immunoactive microglial cells. The modulation of microglial activation, phagocytosis, and secretion by VIP is a promising therapeutic option for the treatment of Alzheimer's disease(AD)

Higher ethical objective (Maqasid al-Shari'ah) augmented framework for Islamic banks : assessing the ethical performance and exploring its determinants.

This study utilises higher objectives postulated in Islamic moral economy or the maqasid al-Shari’ah theoretical framework’s novel approach in evaluating the ethical, social, environmental and financial performance of Islamic banks. Maqasid al-Shari’ah is interpreted as achieving social good as a consequence in addition to well-being and, hence, it goes beyond traditional (voluntary) social responsibility. This study also explores the major determinants that affect maqasid performance as expressed through disclosure analysis. By expanding the traditional maqasid al-Shari’ah,, we develop a comprehensive evaluation framework in the form of a maqasid index, which is subjected to a rigorous disclosure analysis. Furthermore, in identifying the main determinants of the maqasid disclosure performance, panel data analysis is used by including several key variables alongside political and socio-economic environment, ownership structures, and corporate and Shari’ah governance-related factors. The sample includes 33 full-fledged Islamic banks from 12 countries for the period of 2008–2016. The findings show that although during the nine-year period the disclosure of maqasid performance of the sampled Islamic banks has improved, this is still short of ‘best practices’. Through panel data analysis, this study finds that the Muslim population indicator, CEO duality, Shari’ah governance, and leverage variables positively impact the disclosure of maqasid performance. However, the effect of GDP, financial development and human development index of the country, its political and civil rights, institutional ownership, and a higher share of independent directors have an overall negative impact on the maqasid performance. The findings reported in this study identify complex and multi-faceted relations between external market realities, corporate and Shari’ah governance mechanisms, and maqasid performance

Control of slope deformations in high seismic area: Results from the Gulf of Corinth observatory site (Greece)

International audienceThe northern coast of the Peloponnesus (Greece) is characterized by high seismic activity related to the Gulf of Corinth opening with an extension rate of 16 mm y− 1. Studies presented in this paper focus on the characterization of links between tectonic and slope deformations on the Panagopoula slope, located on the southern coast. The approach is centred on qualitative and quantitative data acquisition based on geological and geomorphological investigations, geophysical imagery by electrical resistivity tomography and slope displacement monitoring. Firstly, we highlight two different types of slope deformation on Panagopoula: a superficial landslide affecting weathered limestone, and a large-scale deformation without global failure expressed in the field. Tectonic features play a major role in these two dynamic processes, taking into account the strong geometrical link between the inherited fractures and gravitational scarps mapped in the field. Secondly, the displacements survey network, distributed on both sides of a significant fault crossing the slope, allows the quantification of slope displacements underlying two components: (i) a gravitational sliding (N010) along the slope, and (ii) a supposed tectonic component (N240)

Deep-seated failure propagation in a fractured rock slope over 10,000 years: The La Clapière slope, the south-eastern French Alps

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Landslides triggered factors analysed by time lapse electrical survey and multidimensional statistical approach

International audienceA temporal imagery of water circulation in a landslide by Electrical Resistivity Tomography (ERT) was conducted to identify spatially and temporally the coupling between rainfalls, consecutive water inflows in a sliding mass, and induced resistivity variations. This work is based on a multi-scale experimental approach applied on the “Vence” landslide (South-eastern France) which is characterised by a sandy-clay sliding mass on a marly limestone substratum mostly controlled by high rainfall events. At the landslide scale, historical, geological and geotechnical data combined with field investigations and the interpretation of three ERT allowed the definition of a geometrical model of the landslide and the calibration of the resistivity values. On the basis of these results, a permanent time lapse ERT survey was designed on a specific part of the landslide, coupled with water level acquisition (piezometric levels) and rain fall events. Results covering a three-month period are showed. The statistical analyses of all the physical parameters measured during the three months of investigation show that the matrix of correlations highlighted strong correlations between the rainfall, piezometric elevation and the resistivity. These first results show an accurate answer resistivity/piezometric elevation that can be associated as a precursor of the reactivation of the landslide

Temporal evolution of weathered cataclastic material in gravitational faults of the La Clapiere deep-seated landslide by mechanical approach

International audienceAfter a few years of research, the observation and the analysis of the deep-seated landslides suggest that these are mainly controlled by tectonic structures, which play a dominant role in the deformation of massif slopes. The La Clapière deep-seated landslide (Argentera Mercantour massif) is embedded in a deep-seated gravitational slope deformation affecting the entire slope, and characterized by specific landforms (trenches, scarps...). Onsite, the tangential displacement direction of the trenches and the scarps are controlled by the tectonic structures. The reactivation of the inherited fault in gravitational faults create a gouge material exposed to an additional mechanical and chemical weathering as well as an increased of leaching. The displacement of these reactivated faults gets increasingly important around the area of the La Clapière landslide and this since 3.6 ka BP. In this study, mechanical analysis and grain size distributions were performed and these data were analysed according to their proximity the La Clapiere landslide and times of initiation of the landslide by 10Be dating. Triaxial test results show that the effective cohesion decreases and the effective angle of internal friction increases from the unweathered area to the weathered area. The whole distribution of the grain size indicates that the further the shear zone is open or developed, the further the residual material loses its finest particles. This paper suggests that the mechanical evolution along the reactivated fault is influenced by the leaching processes. For the first time, we can extract from these data temporal behaviour of the two main mechanical parameters (cohesion and angle of internal friction) from the beginning of the La Clapiere landslide initiation (3.6 ka BP) to now

Morphologic assessment of mandibular reconstruction by free fibula flap and donor-site functional impairment in a series of 23 patients

SummaryIntroductionMicro-anastomosed free fibula flap is an attitude of choice in mandibular defect repair in oncology, enabling effective functional rehabilitation. The present study assessed donor and recipient site morphology and donor-site sequelae.Patients and methodsThe study consecutively recruited patients undergoing mandibular resection with free fibula flap reconstruction in our centre between December 2003 and September 2008. Assessment on adapted scales was performed by two independent expert physicians and patient self-assessment.ResultsOut of 49 mandibular reconstructions performed in the centre over the 5-year study period, 23 patients free of recurrence were included. Satisfaction rates were 73% for the recipient site and 70% for the donor-site, with patient/expert agreement of 47% and 49.5% respectively. Donor-site impact was mainly in terms of reduced ankle range of motion (43% of cases) and flexion strength (39%) and discomfort in running (35%) and walking (26%). Risk factors for dissatisfaction were more than 5% weight loss at admission for recipient site dissatisfaction (patient, P=0.012; expert, P=0.046), and skin graft for donor-site dissatisfaction (patient, P=0.04; expert, P=0.035).ConclusionFree fibula flap was associated with high satisfaction rates, but non-negligible donor-site impact

Paraglacial gravitational deformations in the SW Alps: a review of field investigations, 10Be cosmogenic dating and physical modeling,

International audienceCatastrophic deep-seated landslides (DSL) are generally considered to be the result of large slope deformations also known as deep-seated gravitational slope deformation (DSGSD). This paper aims to build a synthesis of multiple studies made in the Tinée Valley (southern French Alps) to assess the geometrical, kinematical, mechanical and chronological relationships between these two gravitational processes. At the scale of the valley, data issued from geological, geomorphological and 10Be dating indicate a clear geometrical link between DSGSD and DSL occurring at the base of the slope and suggest that gravitational slope evolution began after the glacial retreat (13 ka BP). This is supported by the example of the well-documented La Clapière slope. A continuous evolution process is characterized geometrically and temporally from geomorphic observations and analogue modelling. Coupling structural, geomorphological, physical and chronological studies allowed us to propose a four-dimensional (4D) deformation model mechanically correlated with progressive failure concept. The validity and variability of this reference site are discussed at the valley scale (taking Isola and Le Pra slope deformation as examples). It allows a rough estimation of the state of slope deformation at the valley scale to be constructed and the slope evolution with time to be considered. This 4D model could then be considered as a reference for other deep-seated gravitational slope deformations in comparable Alpine valleys